Fluorinated sym.-triazine derivatives



United States Patent US. Cl. 149-109 15 Claims This application is a continuation-in-part of our copending application Ser. No. 856,877 filed Dec. 2, 1959, now abandoned.

This invention relates to highly fiuorinated compounds of carbon and nitrogen and particularly to certain very highly fiuorinated high molecular weight oxidizing agents containing fluorine, nitrogen and carbon, and including N-heterocyclic ring systems.

It is well known that fluorine is the most electronegative element and therefore is an oxidizing agent with very high potential. However, fluorine is a gas under ordinary conditions of pressure and temperature requiring rather special techniques in its manipulations, but particularly the very fact that it is a gas limits the extent to which its high oxidizing potential could otherwise be utilized for use Where high energy output is required. Among such possible uses are a number of industrial processes where high oxidizing potential can extend the range of application, increase rate of output and the like. Many industrial requirements have heretofore been met in a more or less satisfactory way by using less powerful and more readily handled oxidizing agents. Bleaching of wood pulp, fabrics, flour and such materials may be mentioned among such uses. However, more active oxidizing agents would be advantageous in such industrial uses if readily handled, permitting shorter process time, use of lower concentration, etc. Another field in which very high oxidation potentials are particularly desirable is in the field of reaction-type propellants where extreme releases of energy are necessary to achieve large thrusts. For such purposes the availability of a stable, nonvolatile, relatively safely handled material possessing even a substantial fraction of the oxidizing capacity of fluorine but still at a high potential would be very desirable in formulating solid propellants.

It is known that the oxidizing potential of fluorine is retained to a-considerable extent in --NF and :NF radicals represented by the structures:

but methods of synthesis of compounds containing such radicals are very severely limited and the introductionof a plurality of such radicals into a molecule has heretofore been extremely difficult if not im ossible.

It is an object of this invention to provide fluorinecontaining compositions having substantial oxidizing capacity. A further object is to provide highly fiuorinated derivatives of polytriazines containing fluorine in oxidizing configurations. A further object of the invention is to provide highly fiuorinated derivatives of compounds possessing a plurality of heterocyclic nitrogen atoms. A still further object is to provide substantially non-volatile oxidants having high oxidizing capacity at a high potential. Another object of the invention is to provide a process for producing the compositions of the invention. Other objects will become evident hereinafter.

In accordance with the above and other objects of this invention, it has now been found, quite unexpectedly, that compositions containing a plurality of --NF and :NF groups are formed by direct fluorination of certain heterocyclic compounds in which the ratio of nitrogen to carbon is greater than 1.0 and not greater than 3.0. These compounds are conveniently derived from compounds containing sym-triazine systems and bearing amino and/ or hydrazine groups as substituents on available sites of carbon atoms.

The simplest compounds containing the sym-triazine structure which are suitable for fluorination by the process of the invention are melamine (I) and trihydrazinos-triazine (II).

Both of these substances can be pyrolyzed to form more complex structures by intermolecular elimination of simple molecules, e.g. ammonia. By heating at 350 C., melamine is thus converted to melam which is believed to have the structure III:

When heated at 400 C., melamine is converted to melem which may have the structure IV:

Other structures have been proposed for melem; for example, those set forth in the report of May, I. App. Chem, vol. 9, June 1959, pp. 340-344, 1959.

This is evidently the triamino derivative of the tri-s-triazine nucleus, (V), otherwise known as the cyameluric nucleus.

The cyameluric nucleus is conveniently represented graphically, particularly for describing more complex structures, by a triangle thus:

It will be understood that this triangular symbol is herein used to represent the trivalent cyameluric nucleus, CsNq, and not a cyclopropane ring.

The triamino derivative of the cyameluric nucleus, designated melem, is thus represented by the graphical formula VII:

VII

V III NH: NH: N Ha N NE and many other such complex structures including those containing twenty or more of the cyameluric nuclei attached to one another through nitrogen atoms, with primary and secondary amino groups being the only positions at which the molecule contains hydrogen atoms. It is further noted that in every case the carbon which is present is attached to nitrogen.

Pyrolysis of trihydrazino-triazine (II) likewise leads to the formation of complex molecules which for convenience are referred to as polymers of trihydrazino-striazine. The structures thus formed may be exactly analogous to those obtained from melamine, but it has not been possible to prove this unequivocally because of difficulties connected with the reacting materials such as their insolub e and unreactive nature, and b c u e hese compounds, including the products of the reaction, are not readily analyzed. Furthermore, at least melon itself appears to occlude air in some manner such that it is removed only with difliculty, and this further renders analysis diflicult and imprecise.

The trihydrazino-tri-s-triazine corresponding to melem and represented by Formula XII is produced by the reaction of hydrazine hydrate with cyameluric derivatives, such as melon, cyameluric chloride and hydromelonic acid; and may also be employed in the fluorination reaction of this invention to provide useful highly fluorinated compounds. Potassiummelonate, represented by 'Formula XHI can also be employed as a heterocyclic reactant for fluorination. Guanamines, such as malonoguanamine; pyroguanazole, guanazo-guanazole and the like, as Well as low polymers derived by heating melamine with phenyl cyanurate, and other complex structures of this type, also can be employed in the process of the invention, to produce highly fluorinated oxidants. Thus, it is noted that the heterocyclic structures contain 5- to 6-membered rings, containing three or more nitrogen atoms in configurations such that all carbon atoms are separated from one another by at least one nitrogen atom.

In order to avoid excessive prolixity in this specification all of the above materials which are fluorinated by the process of this invention will be referred to as heterocyclic reactants which term will be understood to include heterocyclic substances which contain carbon and nitrogen, the cyclic carbon atoms being bonded only to nitrogen, as hereinabove exemplified both broadly and specifically; as well as the mixtures which may be formed among these compounds, owing to the specific methods for their preparation.

It will be seen that one of the critical characteristics of these heterocyclic reactants is that cyclic carbon atoms are never bound to other cyclic carbon atoms. A further feature is that except for that which may be attached to bridging methylene groups, all of the hydrogen atoms are attached to nitrogen. Surprisingly, in view of the general insolubility and relative inertness of these substances, especially those containing several cyarneluric nuclei, it is found that it is possible to replace substantially all of the hydrogen atoms they contain by fluorine atoms, by direct fluorination using elemental fluorine, whether the heterocyclic reactants are present as solids or as suspensions in a suitable liquid inert to fluorine. It appears from what can be determined from the stoichiometry of the reaction and the analytical values obtained on the products that the reaction not only replaces substantially all of the hydrogen atoms by fluorine atoms but that in addition greater or lesser amounts of fluorine combine with the heterocyclic reactant by addition to carbon-nitrogen double bonds of the triazine or cyameluric nucleus or other heterocyclic rings which may be present (as in the case of the pyroguanazole nucleus, for example), and possibly react as well to bring about fluorinolysis of amine linkages with the consequent loss of nitrogen atoms. The resultant products, which vary over certain ranges in fluorine content, are conveniently described as hyperfluorinated heterocyclic compounds. The term hyperfluorinated is employed to signify that there is a high fluorine content but not necessarily theoretical saturation w th fl o ne. There is reason o be i ve hat not all of the double bonds present in the reactants add fluorine and furthermore complete saturation with complete fluorinolysis would be expected to result in complete decomposition of the heterocyclic reactants to produce CF NF and HF. Surprisingly, the reaction stops well short of this to produce white to yellowish, non-volatile amorphous materials, which may be non-crystalline to sticky solids or oils, in which the fluorine content may vary from about 42 percent to about 67 percent by weight and the oxidizing capacity is from about 14 to about 35 milliequivalents of iodine per gram. Oxidizing capacity is determined using standardized solutions of potassium iodide in aqueous acetonitrile. The compositions of the invention are shock-sensitive, but are usually not so impact sensitive that a 2 kgm. weight falling through 1 inch (2.5 cm.; DT =2.5) will cause detonation although greater drops or greater weights may result in detonation. They can accordingly be manipulated using suitable precautions, and thus they are different from many known materials having high oxidative capacity which cannot safely be manipulated. It is, of course, only normally prudent to exercise considerable care under all circumstances since, when detonated, materials of such high energy content produce very violent explosions and in fact are so powerful as oxidizing agents that they can ignite many common organic substances. Extreme care should be exercised in detonating quantities over about milligrams for testing.

In the analysis of the above hyperfiuorinated products it appears that each available fluorine atom (fluorine attached to nitrogen in NF and is removed by iodide ion with a 2 electron change in valency, i.e. F-2I, and not as one might presume on an atom for atom basis. From this and from analytical results derived from analysis of hyperfiuorinated heterocyclic products of the invention it does not appear that all bonds have been fully saturated with fluorine and the products presumably still retain a certain number of carbon-nitrogen double bonds.

The compounds of the invention are thus seen to be amorphous, shock-sensitive compounds which contain heterocyclic ring systems in which carbon is bonded only to nitrogen, which compounds contain carbon, nitrogen and fluorine in the ratio C:N :F which have an oxidizing capacity of from about 14 to about 50 milliequivalents of iodine per gram, and have molecular weights ranging from about 280 to 4000. They consist essentially of polyfluorinated heterocyclic ring systems which contain ring structures containing individual cyclic units of at least three nitrogen atoms and not more than 3 carbon atoms in a configuration such that any cyclic carbon atom is separated from any other cyclic carbon atom by at least one nitrogen atom. These rings may be fused with each other or otherwise joined in a manner substantially the same as their interconnection in the starting heterocyclic reactants when several such units are present. Attached to the heterocyclic rings of these products are -NF groups, derived, for example, from the amino, hydrazine and other ring substituents in the starting materials, while at least a portion of the ringnitrogen atoms, together with secondary amino bridging groups believed to be present in the original structure, are also fluorinated to yield =NF groups. There is thus present a plurality of nitrogen to fluorine bonds in NF and groups. Such compounds arcs illustrated by the following:

CF: F 1nd F-NF: t: F

\F FaN-(BF F bro MW.=282 MW.=460

in which the nuclei will be recognized to be respectively, triazine and cyameluric ring structures. These materials are formed together with concomitant products, respectively from melamine (Example 66) and melem (Examples 49-53).

The structures of a number of heterocyclic reactants used as starting materials in the process of the invention are described in the reference work s-Triazines and Derivatives, L. Rapoport et al., Interscience Publishers 1959, New York.

The compounds of the invention are white to yellowish solids or semisolids, or oily liquids, at ordinary temperatures. They contain substantially no residual hydrogen in the molecule, and, when they are solids, are insoluble in the common organic solvents, but can be dispersed in a variety of inert solvents and are generally soluble to some extent in fluorocarbon solvents. The oily, liquid products are soluble in such solvents as methylene chloride, fluorotrichloromethane and the like. The solid materials do not melt, but decompose on heating; however, certain of the liquids may be distilled with great caution under highly reduced pressure. When mixed with substances which can be oxidized, such as an organic polymer, and ignited as by means of a squib, they burn with intense heat and the formation of large volumes of gases. When treated wtih water, or exposed to moisture, these fluorinated compounds hydrolyze with loss of their oxidizing power.

The infrared spectrograms of the compounds of the invention, when carried out by using a mull of the compound in mineral oil, where solid products are obtained, and by using a capillary film of the liquid product pressed between sodium chloride plates, show the following recognizable major absorption peaks: 5.5 to 6.4,u. (C=N which diminishes in intensity as the C=N bonds are more completely fluorinated), 7.5-9.4,u. (C-F, frequently broad, with a summit at about 8.25 diminishing in intensity and width as the numbers and types of CF bond diminish and 9.7 to 11.2p. (region with absorption assigned to NF groups characterized by increasing intensity as the number and kinds of NF groups increase). In addition, absorption at 7.2 1. (unassigned) frequently is found.

Nuclear magnetic resonance values, determined by the method of Filipovich et al., J. Phys. Chem., 63, 761 (1959) indicate absorption at 19 to -24 due to NF groups on a saturated carbon atom, at +60 to +1054 due to CF and -NF groups and at 5 to due to a single fluorine atom on a saturated carbon atom.

Broadly speaking, the process of the invention is carried out by treating a heterocyclic reactant compound as described herein, for example, a reactant containing an s-triazine nucleus or a cyameluric nucleus, or a triazole nucleus, or the like or a plurality thereof, with elemental fluorine. For best results, the starting materials should be substantially anhydrous, to avoid destruction of =NF groups after their formation. The process is carried out at a temperature in the range of about 100 to 100 C. or even somewhat higher, and the fluorine is conveniently introduced under slight positive pressure, or if closed vessels are used, pressures up to 100 p.s.i. can be used. Preferably, the fluorine is diluted with nitrogen or other inert gas such as argon or helium, or a Freon, such as dichlorodifluoromethane and the like, to give about 0.1 to 100 percent of fluorine in the gas stream. Undiluted fluorine can be used in any of the procedures described, using great caution and slow addition when working with solid, finely powdered undiluted heterocyclic reactants; but residual fluorine should always be flushed out of the reactants and the apparatus, using dry nitrogen or the like, to avoid unpleasant and toxic exposure to fluorine as well as untoward effects owing to the strong oxidizing power of this substance. The apparatus used is preferably constructed from Monel metal or copper. The solid, in finely divided form, is placed in a suitable container, such as a boat, or spread on a sheet or plate, and is thus contacted with fluorine for a period ranging from about 10 minutes to about 6 hours. In general, pure copper vessels are preferable to vessels made of stainless steel. Plates made of a fluoride, e.g., barium fluoride, may be employed in some instances. Generally speaking, once the process has gone to completion, no further fluorine reacts, so that continuation of the flow of fluorine is not deleterious; but excessive exposure to fluorine, of the order of 12 hours or more, should be avoided to eliminate the possibility that degradative reactions may occur. Preferably, the reaction mixture is maintained at a temperature in the range of about to +40 C., and the fluorination process is continued for not to exceed 5 hours. If desired, an inert liquid suspending medium can be used to suspend the finely divided heterocyclic reactant, and the fluorine gas with or without a diluent gas is then bubbled through the suspension. Thus, for example, fluorine-inert liquids such as perfluorinated hydrocarbons, e.g. perfluorooctanes, perfluorohexanes, and the like; perfluorocyclohexane, perfluorinated cyclic ethers such as perfluorobutylfuran; perfluorinated tertiary amines such as trisperfluoro-n-butylamine; and the like can be used. Commercially obtainable fluorocarbons may contain an amount of material which is not inert toward fluorine, and in such cases, fluorine gas is passed through the selected fluorocarbon liquid for a time in small amounts suflicient to render it substantially completely inert toward fluorine. When an inert diluent is employed in the process of the invention, the hyperfluorinated reaction product generally dissolves in the diluent.

In the procedure where no solvent is used, the product of the process is ready for use directly following removal of the excess of fluorine gas. Where solvent is employed, any insoluble material is removed by filtration and the product is recovered by evaporation of the solvent, preferably under reduced pressure.

Without wishing to be bound by the theory, it seems that the success of the process of the reaction may be due to the initial interaction of the heterocyclic reactants and fluorine to form fluorine-carrying substances which serve to promote the smoothness of the reaction through formation of precursors of the final products, which are then hyperfluorinated, mitigating excessive fluoroinolysis.

Having thus described the invention in broad general terms, it is now more specifically described by means of non-limitative didactic examples intended to show the best mode presently contemplated of practicing the invention. It is to be noted that in almost all cases, reactions must be carried out with due care for the toxic nature of fluorine and other volatile materials and the explosive properties of the products. In the examples, gas mixtures are set forth in percentage by volume unless otherwise specified, while analysis figures are set forth in percentage by weight.

EXAMPLE 1 Two procedures are particularly convenient for the preparation of melon. They differ in that melon is obtained either as a compact yellow powder or as a light yellow flutfy powder. This example illustrates the former procedure.

= Pseudothiocyanogen is prepared by passing chlorine gas through a solution of 1200 g. of potassium thiocyanate in 2.5 l. of water at 60 C. using an ice bath to remove heat as liberated until no further precipitation occurs. The dark orange pseudothiocyanogen is isolated by filtration, washed several times with boiling water and dried at 120 C. to constant weight. Pseudothiocyanogen is converted to melon by heating first in an evaporating dish until no further flammable products are removed and the residue is yellow, followed by heating in an open flask until no more volatile material distils. The final temperature is about 550 C. This last step requires about 1 week. The product contains 350% C, 2.0% H and 61.2% N which agrees reasonably well with the values calculated for a molecule composed of three cyameluric nuclei. This is the compact form of melon.

EXAMPLE 2 Mercuric thiocyanate is prepared by metathetical precipitation of aqueous solutions of mercuric acetate and potassium thiocyanate. After drying in vacuo (using a mercury vapor pump to lower the pressure), the mercuric thiocyanate is heated in a very large (oversize) container until it decomposes to give a very voluminous yellow and black product. This crude product is crushed in a mortar and heated in vacuo to remove mercuric sulfide. The yield on a weight basis is very low because of the heavy mercuric sulfide formed. The product is further heated in vacuo using the direct flame of a gas burner. (The temperature rises to about 525 C.). The resultant melon is a light yellow flufly powder. Analysis shows the presence of 34.0% C., 1.8% H and 57.2% N. The total percentage of C, H and N is less than 100, probably because of the presence of adsorbed oxygen, since the total of analysis percentages approaches 100% when the material is fully flushed with helium.

EXAMPLE 3 This example illustrates the process in which melon is fluorinated without a suspending liquid.

In a copper boat are placed 42 mgm. of the flufly melon of Example 2, the boat is placed in a 1 inch by 14 inch nickel tube having a polytetrafluoroethylene rupture disc at one end, and a stream of dry prepurified nitrogen is forced over it to displace air since the fluorine subsequently introduced may facilitate explosive oxidations by oxygen and additionally it is found that the fluorination reaction is inhibited by as much as 5 percent of oxygen based on the amount of fluorine present. Fluorine (commerically available, pure) is introduced (using Monel metal fittings) into the nitrogen stream to give a concentration of 7% by volume and the stream of fluorine and nitrogen is passed over the melon for about 2.8 hours at 25 C. The fluorine is discontinued and nitrogen is continued for a few minutes to remove residual fluorine in the apparatus. The apparatus is opened and the copper boat containing the gummy yellow, solid fluoromelon is removed. It will be understood that the term fluoromelon is employed for convenience to designate fluorinated or hyperfluorinated melon and is an empirical rather than systematic name. There has been an uptake of 32 mgm. of fluorine. Decomposition of a sample by the procedure reported by Senkowski, Wolliski and Shafer in Analytical Chemistry vol. 31, pages 1574 to 1576 (1959) followed by titration with standard thorium nitrate solution using sodium Alizarin Red S as indicator shows 47.5% by weight of fluorine. Reaction of a sample with excess potassium iodide in acetonitrile followed by titration using standard iodometric procedures shows that the fluoromelon has an oxidizing capacity equivalent to 22.8 milliequivalents (meq.) of iodine per gram.

Table 1 sets forth the results of a number of repetitions of the process for preparing fluoromelon, using various amounts of reactants and reaction times. The procedure set forth above is repeated, employing fluorine concentrations from about 4 to about 22% and reaction times varying from about minutes (0.16 hours) to about 160 minutes. In all cases the temperature is about room temperature, i.e. C. The melon used was prepared by the process of Example 2, except in Example 15 where melon produced by the process of Example 1 was used.

The yield is not dependent on the large excess of fluorine, since in another experiment using 1000 mgm. of the same melon and 17.6 g. of fluorine, 240 mgm. of insoluble material is recovered and the fluoromelon weighs 1640 mgm. The latter has a somewhat higher oxidizing capacity of about 23.0 meq. of iodine per gram, but contains somewhat less fluorine. Examination of TABLE 1 Weight Fluorine Percent F2 Oxidizing Percent start uptake in gas Time capacity Example (mgm.) (mgm.) stream (hrs.) (meq.) I/g. F C N DIKcm.)

1 Yellow, sticky to gummy solid. 1 Yellow solid. 3 White, flufly solid. 4 Questionable accuracy.

EXAMPLE 16 this material by m-fra-red absorption spectroscopy and This example illustrates the preparation of fluoromelon by fluorination of a suspension of melon in an inert liquid.

A suspension of 300 mgm. of melon (compact form of Example 1) in 75 ml. of a perfluorooctane is placed in a Monel metal flask having standard taper connections and fitted with inlet for gas from a mixing manifold, a thermocouple and a vent line passing through a Monel metal condenser. All leads for gases through which fluorine is to pass are constructed of Monel metal and measurement of nuclear magnetic resonance confirms the presence of -NF ,=NF and groups.

In Table 2 are shown the reaction conditions and results obtained when the above procedure is repeated to produce a number of preparations of fluoromelon. In all cases a very large excess of fluorine is used. The melon used was prepared by the process of Example 1.

TABLE 2 Liquid product analyses Wt. Wt. Wt. solid liquid Oxidizing Percent start, phase, phase, Time Temp., capacity, Ex mgm mgm. mgm. (hrs) C. mgm. F C N 1 Inconsistent with other data which indicate a fluorine content of at least 46%.

a polytrifluoromonochloroethylene rotameter tube with a Monel metal ball is employed to gauge rate of flow. Nitrogen is passed through the suspension for a few minutes to flush oxygen from the system and fluorine is gradually introduced into the stream and the nitrogen concentration decreased until undiluted fluorine is passing through the suspension. This procedure is reversed toward the end of the reaction, to decrease the concentration of fluorine to zero, so that after 3.5 hours a total of 22.5 g. of flourine has been passed through the suspen 5 sion. After flushing with nitrogen, the suspension is filtered through a sintered glass filter to remove 160 mgm. of insoluble yellow powdery material which appears to be only slightly changed melon, but may contain as much as 15-20 percent fluorine. The filtrate is evaporated carefully in vacuo to give 220 mgm. of colorless, viscous liquid fluoromelon which, on analysis, is found to contain 52.0% F, 15.5% N. The fluoromelon thus prepared has an oxidizing capacity of 22.4 meq. of iodine per gram. The impact sensitivity DT is 5.8 cm.

The products obtained are all light yellow, shock-sensitive, viscous liquids and have DT values ranging from about 1.8 to 10 cm. When solid phases obtained above are again fluorinated under similar conditions, further amounts of oily hyperfluorinated products are obtained which are substantially identical with those shown above.

The amount of perfluorooctane or other suspending liquid used in the process can be varied over a wide range without having any apparent effect on the reaction and in general is more a matter of convenience for the size of reaction vessel used. Initially, at least, reaction appears to occur with the heterocyclic reactant as a solid. When reaction has proceeded sufficiently, solution occurs and further reaction is apparently very slight. The process used hereinabove has the advantage over the procedure of Example 3 that there appears to be dissipation of energy released, e.g. heat, during reaction and it may be for this reason that somewhat higher percentages of fluorim: and oxidative capacity are achieved. Furthermore the sticky products obtained by the process of Example 3 probably interfere mechanically with the reaction so that fluorination ceases sooner than when portions are removed by solution.

The procedure of Example 16 is repeated using other heterocyclic reactants in amounts and under varying con- 1 2 EXAMPLE 59 A stream of 100% fluorine is bubbled through a suspension of 3 g. of guanazoguanazole in 160 ml. of fluorotrichloromethane at 74 to -56 C. during 6 hours at a rate such that 2 moles of fluorine is employed. The solui ii gg g lz ggjg i i 1 5:? E 3 tion is filtered through sintered glass to remove 2.9 of a g O h y y partially fluorinated (18.5% fluorine by analysis) gua OS or convenience a nazoguanazole. Evaporation of the solution provides a ver viscous yellow liquid containing 43.2% of fluorine a e Formulall giig s polymer and having an oxldatron equlvalent of 21.8 m1ll1equ1valents THTTAItrihydrazino tri triazine (Formula XII) of 1od1ne per gram. D1st1llat1on at less than 1 mm. of Hg KM potassium melonate (Formula XIII) pressure provldes hyperfluormated guanazoguanazole as PDTPZPheHOXy diamino trizaine polymer (formed by a moblle yellow l1qu1d contalnlng about 26.3 rmlhequlvheating at 355 C. until no further evol-ution of phenol) alents g lodlge per gram g j absorgtloli i g e 5 5 5 copy s ows t e presence o mtrogen to uorlne on s. f rmaldeh de re 1n MFR Melamme y S The DT value is 1.8.

It will be noted that molecular Weights (determined by EXAMPLE 60 measurement of vapor pressure depression in methylene The above procedure employed for the fluorination of chloride) average about 525-600. guanazoguanazole is repeated with 3.0 g. of guanazole.

TABLE 3 Percent; Oxidizin Heterocyclic Reactant Liquid prod- Temp., 55 555155, Example reactant used, rngm. uct mgm. Time (hrs.) F C N meq.I/g. M.W

3, 2 3 2 4;). g 19. 1 5 25 5 18.0 .1 1,000 790 3. 25 25 52. 8 1s. 2 5 132 13 5 11000 1, 450 1. 05 25 52: 4 1s: 2 I0 3, 500 750 4. 33 17-35 55. 2 3, 500 1, 330 0. 75 25 51. 2 19.1 3,000 470 3. 0 25 52. 6 4, 1 0 2, 22 1 -38 53. 5 17. 5 5 51.0 19.4 3, 500 130 4. 82 25 55. s 2, 520 1, 250 4. 25 27-38 3,000 1, 200 2. 50 10 52. 6 15. a 3,500 1,440 6. 25 25-27 51. 1 15. 5 3,000 920 4. 0 16 to -20 54. 2 a, 000 1,870 2. 33 25 51. 2 15. 7 2,000 ,970 4. 0 50-50 51. 5 17. 4 s3 23 2 -82 -3 35 3: 000 11540 2150 20 54: e 1514 3, 000 3, 620 2. 6 25 52. 3 17.4 1,000 610 3. 0 1.5-15 54.0 3, 000 1, 340 5. 0 27-30 54. 3 17. 0

38% of fluorine present as NF: groups on basis of nuclear magnetic resonance spectrum.

3 Heat of combustion 1,860 calories per gram.

All of the fluorinated products are light yellow shocksensitive, viscous liquids having DT values ranging from about 1.2 to 10 cm.

EXAMPLE 57 The process of Example 3 is repeated using 321 mgm. of succinoguanamine in a copper boat and treating for 1.46 hours with a 5.6% by volume stream of fluorine in nitrogen gas. The yellow gummy solid product weighs 374 mgm. It is found to have a DT value of 50 cm. and contains 45.3% F, 27.9% N and 23.1% C. The oxidizing capacity is 14.1 rneq. I per gram.

EXAMPLE 5 8 A 3.0 g. sample of pyroguanazole (prepared by the procedure of Hofrnan and Ehrhardt, Ber. 45, 2731 (1912)), is subjected to fiuorination in suspension in 150 cc. of perfluorooctane using the procedure of Example 16. The reaction is carried out at 16-17 C.'for about 1.5 hours. A yellow solution containing some solids is obtained. It is filtered to remove 2.7 g. of residual solid. Upon evaporation of the solution, 0.35 g. of a very viscous yellow oil is obtained, having a DT value of 3.8 cm., and having an oxidizing value of 14.9 milli-equivalents of iodine per gram.

4 42% of fluorine present as N F2 groups on basis of nuclear magnetic resonance spectrum.

Hyperfluorinated guanazole is obtained containing 40.3% of fluorine and having an oxidation equivalent of 12.1 milliequivalents of iodine per gram. The DT value is 3.8.

EXAMPLE 61 /N=N F20 F-NFz characterized by molecular weight (found: 186; calculated: 194) and by absorption bands in the infrared at 7.6-8.6 (assigned to CF), 9.6a (assigned to NF) and 10.0-10.6,2 (assigned to NF CF=). Fluorine-19 nuclear magnetic resonance a'b- 13 sorption is found at -22.1 (NF +8354: and 84.7 (CF +104.8 (NF) and +115.8 (CF).

EXAMPLE 62 Melamine above or in combination with HF or NaF as described in subsequent examples, is reacted with fluorine in a copper boat in a pressure tight iron tube connected so that off gases pass through an iron pipe maintained at 25 C. containing dry sodium fluoride to remove hydrogen fluoride and are then condensed in a glass trap at liquid oxygen temperature. The unreacted fluorine is permitted to escape. After completion of the reaction, the system is exhaustively flushed with dry nitrogen (8-16- hours) to sweep all products having even relatively slight volatility into the glass trap. The reaction products are then separated into what are designated as gaseous or volatile components and liquid products, by evaporation at 25 C. at 50 mm. of Hg pressure. The liquid products remain in the glass trap, the volatile products distil and are condensed in a second trap at liquid air temperature. The volatile products include mostly fragments of the molecule comprising one carbon atom and from 1 to 3 nitrogen atoms with from 4 to 7 fluorine atoms and also the cyclic compound perfluoro-s-triazine which exhibits nuclear magnetic resonance absorption at +87.84, (assigned to the CF group) and at +89.15, (assigned to the NF group) and infrared absorption with principal bonds at 7.6g, 7.8g, 8.1 8.5g, 9.3,u, 9.8,u, 10.6,u, and 10.9 4.

In another preparation a boat is charged with 1.2 g. of melamine and placed in the pipe maintained at -18 C. Fluorine is introduced at 5.5% concentration in nitrogen for 1.5 hours, then at 9.1% for 2.0 hours and the tube is flushed with nitrogen for 1 hour while the temperature rises to 25 C. The tube is cooled to 10 C. and fluorine is again introduced at 9.1% for 95 minutes and then at 21.6% for 40 minutes while the temperature is held at 7 C. A total of 0.152 mole of fluorine is thus passed over the melamine. The products are separted as above to give 0.91 g. of the liquid relatively non-volatile material and 0.64 g. of residue in the boat. The liquid material is found to contain 10.3% C; 23.5% -N and 68.3% F and an oxidation equivalent of 27.8 milliequivalents of iodine per gram. The empirical formula is calculated to be C N F The refractive index is n =1.3260. DTg 1.8. Nuclear magnetic resonance absorption shows that approximately one half of the fluorine is present in -NF groups (absorption at about 20).

EXAMPLE 63 The above procedure is repeated employing 2.35 g. of melamine trihydrofluoride and more vigorous conditions as follows. Fluorine is employed for 90 minutes at 9.1% concentration, for 13 minutes at 21.6%, for 30 minutes at 32.3% and finally for 30 minutes at 50.1%. The temperature is increased from C. during the first stage to C. during the second stage and to 15 C. during the last hour. A residue of 0.17 g. remains in the boat and 1.43 g. of liquid nonvolatile product are obtained. Elemental analysis shows that the latter contains 10.3% C; 24.7% N; and 65 .0 F, and it has an oxidation equivalent of 29.4 milliequivalents of iodine per gram. The empirical formula is calculated to be C N F EXAMPLE 64 The procedure of Example 62 is repeated employing an intimate mixture of 1.70 g. melamine and 10.0 g. dry sodium fluoride, using 9.1% fluorine for about 14 hours (total 0.26 mole) and temperatures from about -55 to 1 C. A large solid residue (11.15 g.) remaining in the boat is a result of the NaF employed which also absorbs HF formed in the reaction. The liquid product amounts to 2.22 g., containing 11.9% C, 20.8% N, and 66.6% F and having an oxidation equivalent of 31.7 milliequivalents of iodine per gram. The empirical formula is calculated to be a 5.5 1o.a-

EXAMPLE 65 The procedure of Example 64 is repeated employing the same quantities of materials with from 5.5 to 9.1% fluorine for 10.6 hours (total 0.15 mole) at 22 C. The liquid product amounts to 1.03 g., found to contain 11.7% C, 25.0% N and 65.7% F on analysis. (-It will be understood that in this and other examples the sum of the percentages may total more than as the result of inherent inaccuracies in the determinations.) The oxidation equivalent is 30.7 milliequivalents of iodine per gram.

Hyperfluorinated melamine as obtained above and in Examples 6264 is directly useful as an oxidant. It is resolved into individual components as described in the following example.

EXAMPLE 66 The hyperfluorinated melamine of the above examples is resolved by gas chromatography employing the tetramer or pentamer of trifluorochloroethylene as the stationary phase and dry diatomaceous earth (commercially available as Chromasorb) as support. Bentzotrifluoride is employed as an internal reference standard as described by Scholly and Brennet, Second Biannual International Gas Chromatography Symposium, Pittsburgh, Pa., pp. 111- 113, June 1959, published by Instrument Society of America, so that compounds can be characterized by corrected retention times, T which are 100 times the ratio of the difference between the uncorrected retention times of the test material and air to the difference between the uncorrected retention times of benzotrifluoride and air.

A total of 3.2 g. of the liquid products produced as in Examples 62-65 above is thus separated in four batches into fractions employing the tetramer as stationary phase at 30 C. Tetramer which tends to be swept through by the nitrogen stream remains as a residue after vacuum evaporation of each pooled fraction. The fractions having T of about 35.1 and 77.5 to 82.5 are obtained in considerable amount and are identified as comprising largely 2-difluoroamino-perfluoro-s-triazine and 2,4-bis(difiuoroamino)perfluoro-s-triazine, respectively.

In a similar separation employing the pentamer at -60 C. as stationary phase 2.64 g. of similar materials are separated in three batches and materials having T of 77.5 to 82.5 and 145.8-l70.9 are obtained in considerable amounts and identified as comprising 2,4-bis(difluoroamino)perfluoro-s-triazine and 2,4,6-tris(difluoroamino) perfluoro-s-triazine, respectively.

The following table shows the characterization of these three compounds as obtained. It will be understood that each is presumably somewhat contaminated with other components of the fluorinated melamine.

TABLE 4.FLUORINATED MELAMINE COMPONENTS NF: NFz F2 (1} FIYI NF Fl]! NF FIT] IIIF F20 FNF2 F20 JFNFQ FzN-CF C F-NF2 N N Structural Formula F F 1 Molecular Weight 282 315 338. Empirical Formula O3FigN4... CaFuNs CgFnNu Formula Calculated from analysis CS ll-lNfi-L- O;F1 N .5 %F as NFz calculated 36.5.... 50. F as NFz found 22.5 39-2 52. F19 nuclear magnetic resonance 4 value corresponding to:

( 3-F +125.6 +123 to 124 +120.9.

=OF2 +86.8 +84 to 87 =NF +892 +84 to 87 +86.1.

EXAMPLE 67 Structural characterization Band .1.)

The compounds of the invention can be employed as oxidizing agents in solid or liquid propellants requiring energetic fluorine. For example, for such purposes, about 13 parts by weight of fluorinated melon having oxidizing capacity of about 22.5 meq.I/grn., 12 parts by weight of an 80:20 copolymer of vinylidene fluoride and perfluoropropylene and 9 parts by weight of amorphous boron are combined with 66 parts by weight of ammonium perchlorate by suspending in very pure ethyl acetate to produce a uniform suspension and poured into heptane to form a precipitate which is removed by filtration. After drying, the resulting flufly mass is pressed into a propellant grain having the desired preselected shape. This grain, when placed in a motor case and suitably bonded to the Walls thereof according to the usual practice, can be ignited by means of a heated wire and produces a thrust of high specific impulse.

What is claimed is:

1. A highly fiuon'nated, amorphous, shock-sensitive oxidant composition consisting essentially of the atoms carbon, nitrogen and fluorine in the ratio of about C:N :F having molecular Weight ranging from about 280 to 4000, containing polyfluorinated heterocyclic systems containing 5-6 membered rings consisting of individual cyclic units, each unit consisting of at least three nitrogen atoms and not more than 3 carbon atoms in configuration such that any one of the carbon atoms which are present is separated from any other carbon atom by at least one nitrogen atom, said oxidant composition further containing a plurality of nitrogen to fluorine bonds in ail-F and -NF groups, and having oxidizing capacity equal to about 14 to milliequivalenst of iodine per gram.

2. A hyperfiuorinated, amorphous, shock-sensitive oxidant composition consisting essentially of the atoms carbon, nitrogen and fluorine, present in the ratio of C:N :F having a molecular weight ranging from about 280 to 4000, containing polyfluorinated heterocyclic ring structure consisting of triazine nuclei, having a plurality of nitrogen to fluorine bonds in I'q F and NF groups, and having oxidizing capacity equal to about 14 to 50 milliequivalents of iodine per gram.

3. A hyperfluorinated, amorphous, shock-sensitive oxidant composition consisting essentially of the atoms carbon, nitrogen and fluorine, present in the ratio of C:N :F having a molecular weight ranging from about 460 to 4000, containing polyfluorinated cyameluric nuclei, having a plurality of nitrogen to fluorine bonds in and NH groups, and having oxidizing capacity equal to about 14 to 50 milliequivalents of iodine per gram.

4. Hyperfluorinated, amorphous, shock-sensitive melon containing a plurality of nitrogen to fluorine bonds in and -NH groups and having oxidizing capacity equal to about 14 to 50 miliequivalents of iodine per gram.

5. Fluorinated melon containing more than about 42% fluorine by Weight determined by elemental analysis fluorine atoms being bonded to carbon and nitrogen atoms.

6. Hyperfluorinated, amorphous, shock-sensitive triamino-tri-s-triazine containing a plurality of nitrogen to fluorine bonds in and NF groups, and having oxidizing capacity equal to about 14 to 50 milliequivalents of iodine per gram.

7. Hyperfluorinated, amorphous, shock-sensitive trihydrazino-tri-s-triazine containing a plurality of nitrogen to fluorine bonds in and --NF groups, and having oxidizing capacity equal to about 14 to 50 milliequivalents of iodine per gram.

8. Hyperfluorinated, amorphous, shock-sensitive potassium melonate containing a plurality of nitrogen to fluorine bonds in groups and NH groups, and having oxidizing capacity equal to about 14 to 50 milliequivalents of iodine per gram.

9. A process for the production of hyperfluorinated oxidants, which comprise interreacting together, under substantially anhydrous conditions and at a temperature in the range of about 100 to +100 C., elemental fluo rine and a heterocyclic reactant composed solely of carbon, nitrogen and hydrogen, the ratio of carbon and nitrogen atoms being greater than 121 and not greater than about 1:3, the heterocyclic rings present in thesaid reactant consisting of individual 56-membered cyclic units of at least three nitrogen atoms and not more than three carbon atoms in configuration such that any one of the carbon atoms which are present is separated from any other carbon atom by at least one nitrogen atom.

10. A process for the production of hyperfluorinated oxidants, which comprises interreacting together, under substantially anhydrous conditions and at a temperature in the range of about 100 to +100 C. in suspension in a fluorine inert liquid, elemental fluorine and a finely divided heterocyclic reactant composed solely of carbon, nitrogen and hydrogen, the ratio of carbon and nitrogen atoms being greater than 1:1 and not greater than about 1:3, the heterocyclic rings present in the said reactant consisting of individual 5-6-membered cyclic units of at least three nitrogen atoms and not more than three carbon atoms in configuration such that any one of the carbon atoms which are present is separated from any other carbon atom by at least one nitrogen atom.

11. A process for the production of hyperfluorinated oxidants, which comprises interreacting together under substantially anhydrous conditions at a temperature in the range of about -100 to +100 C. and in the substantial absence of oxygen, elemental fluorine and a finely divided solid heterocyclic reactant composed solely of carbon, nitrogen and hydrogen, the ratio of carbon and nitrogen atoms being greater than 1:1 and not greater than about 1:3, the heterocyclic rings present in the said reactant consisting of individual 56 membered cyclic units of at least three nitrogen atoms and not more than three carbon atoms in configuration such that any one of the carbon atoms which are present is separated from any other carbon atom by at least one nitrogen atom.

12. A process for the production of hyperfluorinated oxidants, which comprises interreacting together under substantially anhydrous and anaerobic conditions at a temperature in the range of C. to +100 C. elemental fiuorine and a finely divided solid heterocyclic reactant containing the cyameluric nucleus and composed solely of carbon, nitrogen and hydrogen.

13. 2,4,6-tris difluoroamino -perfluoro-s-triazine.

14. 2,4-bis (difluoroamino)-perfluoro-s-triazine.

15. 2-difluoroamino-perfluoro-s-triazine.

References Cited Hoffman et al., Chem. Reviews, vol. 62, pp. 12 to 18 (1962).

LELAND A. SEBASTIAN, Primary Examiner US. Cl. X.R. 

1. A HIGHLY FLUORINATED, AMORPHOUS, SHOCK-SENSITIVE OXIDANT COMPOSITION CONSISTING ESSENTIALLY OF THE ATOMS CARBON, NITROGEN AND FLUORINE IN THE RATION OF ABOUT C:N(1.5-4), HAVING MOLECULAR WEIGHT RANGING FROM ABOUT 280 TO 4000, CONTAINING POLYFLUORINATED HETEROCYCLIC SYSTEMS CONTAINING 5-6 MEMBERED RIGS CONSISTING OF INDIVIDUAL CYCLIC UNITS, EACH UNIT CONSISTING OF AT LEAST THREE NITROGEN ATOMS AND NOT MORE THAN 3 CARBON ATOMS IN CONFIGURATION SUCH THAT ANY ONE OF THE CARBON ATOMS WHICH ARE PRESENT IS SEPARATED FROM ANY OTHER CARBON ATOM BY AT LEAST ONE NITROGEN ATOM, SAID OXIDANT COMPOSITION FURTHER CONTAINING A PLURALITY OF NITROGEN TO FLUORINE BONDS IN 